Liquid coating devices



Jam, 12, 1965 R. H. PARKER LIQUID COATING DEVICES 2 Sheets-Sheet 1 Filed Aug. 25, 1961 I/////////I/I/I//// I/I/IJ k Jan. 12, 1965 R. H. PARKER 3,

LIQUID COATING DEVICES Filed Aug. 25. 1961 2 Sheets-Sheet 2 \Q; v -37 6' 39/ \fi C l 55 v a! a 63 65 3,165,425" V LIQUID COATWG DEVICES Raymond H; Parker, 55 Warren Ave, Plymouth, Mass. Filed Aug. '25, 1961, Sen-No. 134,026

3 Claims. (Cl. 118 -252) The present invention relates ingeneral to liquid coating devices, and especially to devices fo'rapplying a film of liquid adhesive;to sheets or strips of thin and flexible material sueh'as paper labels or the like, or to larger sheets. of material such as are used in'covering books.

These devices are herein termed label pasters for present purposes.

The invention is more particularly an improvement'in the label paster of my previous Patent No. 2,573,052, granted Oct. 31, 1951, and has the object of simplifying the construction and use of such prior device. Thus,

'the present invention aims to provide a flat feed table to move the excess quantity of adhesive normally picked up by the roller and leave the desired thickness of the film of adhesive on the roller, so as to suit the consistency of the particular adhesive employed; Another object is to provide a guide of simplified'form forv holding down the label or strip against theroller, and one which will give more perfect' contact of the label against the roller and hence more complete coverage of the label through transfer of the adhesive from the rollers surface to the label, and to provide simpler and easier adjustment of such guide'for different thicknesses, stiffness, or consistencies of the paper or other material composing the label.

To make possible the use of a flat feed table, corresponding improvements are made in the label guiding means and the adhesive-stripping devices for the applying roller.

Toattain greater ease of adjustment of the positions of the guide audof'the scraper, preferablythese two adjustments are-correlated so thatthey are made by one setting which for simplicity is done by. mounting them fixedly on the fiat feed table and arranging the feed table so that it may be tilted about an axis so placed as to set the guide and scraper closer to or further from the surface of the roller as the particular stock and adhesive used may require. While the adjustment of the guide which directs the label or sheet against the roller is relatively not critical, the adjustment of thescraper is considerably more so, as it is necessary to maintain'it in substantially parallel relation to the concave surface ofthe roller throughout the entire length of the latter. [Such uniform spacing, or constant width of the gap throughout the length of the roller, is needed both to apply a film of adhesive of .the right thickness anduniformity to the label, and also to prevent the adhesive from accumulating and building up a thick coating on the'end portions of therollers surface which lie outside the paths of the margins of the labels as fed through the device and which hence" are not stripped down by the transfer of the adhesive to the successive labels. If the glue or pasteiis thus allowed to increase. the effective diameter of the end-portions of the roller, it interferes with the feed of the labels by building up till. it leaves insufficient space for the labels to pass if they are occasionally fed a bit off-center by the user, resulting in jamming, and by wiping ofi onto the guide itself where it causes the "labels to stick to the guide, also with, resultant jamming, and. to betransferred tothe face of the label and smeared thereover in applying the label.

The novel adjustment of the scraper setting by pivoting the feed table overcomes the difficulty otherwise inherent in using a sliding adjustment of the scraper, namely that the glue or paste sets up on and in the guideways or other supporting surfaces which such method requires, and makes the adjustment difficult or troublesome. the whole range of adjustment needed for the gap is normally about A(; inch, the pivotal rnounting'of the feed table about a horizontal axis near .the roller makes easy, a fine adjustment of the spacing of the scraper, such as would be measured'in hundre'dths of an inch, by a much simplified movement of the remote end of the feed table. It permits'this tilting of the table to be effected in predetermined and indicated amounts, throughlifting and lowering such end by a movable wedge, herein a cam whose angular displacement is shown by'an index moving over a scale fixed on the reservoir or tank for the adhesive, or other part. g

Other objects of the invention, and the manner of their attainment, are as set forth hereinafter.

An illustrative embodiment of the invention is shown in the accompanying drawings, in which FIG. 1 is a plan view of the label paster, showing the driving means for. the roller.

FIG. 2 is a side elevation of the device, partly in section, the driving motor being omitted. FIG. 3 is a vertical section on line 33 of FIGQl. FiG..4 is a vertical section on line 4--4-of FIG. 1.

The improved liquidcoating device comprises a rectangular tankl tohold the liquid adhesive, open at the top andhaving a bottom.2v of inverted V-shape with the ridge 5 at the apex of the V extending longitudinally of the tank, the tank preferably being of plastic material either assembled from sheet. stock or molded in one piece, as desired. i I The adhesive-applying roller 7 is mounted to dip into the adhesive in the tank, being supported by means of its integral web 9, located at mid-length, upon a' shaft 11 freely rotatable in bushings 13'fixed in the side walls of the tank, the shaft being held from endwise movement by a collar 15 fixed on one endby a set screw, and by a cotter pin 17 put. through the shaftand bearing against the flanged end of the adjacent bushing 13. The roller 7 is positioned on shaft 11 with its ends equidistant from the respective side walls of the tank by spacersl9 whose flanged inward ends 21 abut against the web 9, against which they are held by nuts 23threaded on the enlarged diameter portion of shaft 11 and bearing against the outer ends of the spacers 19.

The roller 7 has its outer or working surface in the shape of a concave spindle whose profile is defined by two right conic frusta disposed with their small ends opposed and joined, theprofile of each cone being slightly concave, as shown in FIGS. 1 and 4. The roller is in: tegral, and is made hollow for purposes of lightness and economy, and also for its action in mixing the adhesive, which flows in and'out of the ends of the cone during its rotation. 7

Driving means for rotating the roller 7 continuously during use is provided by a smallelectric motor 25 supplied with current viav leads 2'] and equipped with reduction gearing 29 whose power output shaft 31 is deta'chably connected to the shaft 11 of the roller bytongue and-slot joint-33, thereby'rotating the roller at reduced speed.

The feed table 35 is a flat sheet, with its plane top surface parallel to the rollers axis, and conveniently made of transparent plastic enabling the adhesive level to be checked visually. It is provided with two wings 37 afiixed to'the lateral edges of the feed table and extending downwardly in close contact with the outside Walls of the tank and pivoted at their lower extremities on studs 39 which are fixed in the ends of the arms and rotatable in sockets Since The end of the feed table '35 is scraper or stripper which determines the wanted. thickness of the film of adhesive picked up by the roller as it rotates "counter-clockwise, FIG. 3, with itslower portion immersed in the liquid adhesive 40 to a depth suffi cie ntto'wetits entire .length. For this purpose, the end of thetable 35 adjacent ithEL IOHEI iS beveled to a chisel,

throughout the entire common length of theroller and of thisedge so as to scrape backthe excess thickness of.

the ,adhesive'41 and leave a coating of uniform thickness on the roller for transfer to the label being pasted. 7

Since different consistencies ofadhesive and different thicknesses of the coating thereof applied to the material being treated are needed for various purposes,,as noted, provision is required for changingthe'width of the gap between the scraping edge 43 and the roller, and thus controlling and limting the depth of adhesive .allowed to 41 formedin and extending only partway through the v side walls of the tank 1.. 7

made to serve as the end, and at thellevel of the bottom of the rims,- and giving opposite the waistv of theroller, is on a longer radius from the axis through'pivots '3 9 than are the two ends of edge 43. Thus it is not geometrically possible to maintain the two surfaces truly parallelandthe gap precisely equal throughout thefull' range of adjustment. But' by.

locating the axis, through pivots 39 vertically below the rims of the maximum diameter of: the roller,.i.e., on the vertical line tangent to the rising side of the rollers the salient a radius about this axis such that itstarcjof swingif continued would pass just below the axis ofthe roller '7, a satisfactory approximation is attained. In

I narrowing the gap, the end-portions of-edge .43 approach remain on the roller by edge 43 for application to the V a label as the latter is fedflatwiseby hand pressure over the top surface oftable and the roller. This'adjustment is accomplished simply in the present device by a cam device in the form of a metallicrod 47 of initially round section which extends at right angles across the tank beneath thefeed table 35 and rotates in half-bearings cut in the top edge of the tank for its reception. Throughout the full width of the feed table this rod is reducedv to half-round section as shown at 49, the thus fiattended portion being uppermost and engaging'with the under surface of the feed table 35. Both ends 51 or rod 47 are bent downward'into parallel and frictionally gripping relation with the respective side walls of the tank 1, so as to retain the rod in any angular position about its main axis which may be given to it. As is obvious, angular movement of the ends 51 counter-clockwise, FIG. 3, about such the surface of roller 7 slightly closer thefmid-portions at a'ndaboutthe. salient 61, with the advantagethatjwith 7 close settings of the gapthe unused adhesive on the outer ends of the roller not overlapped by the'centrally-fed label is kept'froin accumulating thereon.

. 'As in my prior patent, the adhesive-applying roller 7 is given its concave shape in order to bend up the lateral margins of the label so as to forma troughor valley in the label extendinglongitudinally thereof, namely in the direction of its movement, to stiffen the sheet, against transverse bending and thus render itimpossible onsubstantially so for the label to adhere'to and follow around the periphery of thef'rol'ler over and in contact with which itfis traveling while receiving the coating of adhesive.

To force .the label into contact with the profile of roller 7 throughout the entire width ofv the label, so as'both to axis causes the righthand edge of the half-round portion 49 to cam the feed table upward with attendant rotation of the table about its pivots 39.

Such tilting of the feed table swings its scraping edge 43 into closer proximity to'thesurface of roller 7. The

higher the end of the feed table is lifted by the cam-49, the narrower the gap becomes,and the thinner the coating of adhesive left on the surface of the roller for transfer to the label by the scraper 43. I

Index numbers. may be inscribed on the side walls of the tank along the arc of swing of the ends'51 of the cam, for easy reestablishment of the setting of the gap found to be best adapted for a given combination of label and adhesive. In practically all normal use of the device, the width of the gap between the scraping edge 43 and the confronting surface of the roller 7 will not exceed ,4 of an inch,but the reduction of this gap needed to work with different consistencies of paper and adhesive would be measured in thousandths of an inch. This micrometric scale of adjust ment is attained by putting the cam 49 at a location substantially twice as far from the pivots 39 as the scraping edge 43 is located. Thus, shifting the angular position of the ends 51 of the cam produces a small change in the elevation of the right-hand end of the feed table which effects a much smallerchange in the elevation of the scraping .edge 43 and in its spaced relation to 'the rollers surface.

The contour of the scraping edge 43 is V-shaped, as

needed to match the shape of the rollers surface at the location where the feed tables bottom plane intersects 1t, and hence the salient 61 of edge 43, the apex of the V,

insure the coating of the whole underside of the label and also to make it take and hold' the desired trough shape which compels it to leave the rolleratatangent, a guide 63 of flat stock, preferably the same'transparent material as feed table '35, is mounted in parallel and spaced relation on thefeed table 35 over the scraper 43 and'adjacent portions of the table; The spacing of the guide from the table is close, of the orderv of inch, established by spacers 65 cemented between. and to these two members at the two ends of the guide. The lower. edge ofthe lefthand or delivery end 67vv of guide 631is given a shape in profile matching the contour ofrroller '7' where the latter is intersected by the extension of the plane of the guides under surface, after the manner described in regard to the scrapingedge '43. The edge of the guide, however, has considerably more clearancexfrom the roller than the scraper. The right-hand edge of guide 63 is V-shap'ed in plan, and undercut as indicated at 69 to guide the label easily beneath it as the label is slid forward by hand along the table and onto the roll. The apex 71 of the V,being below the low point at'the waist of the roller, insures that even the portion of the label traveling over the waist is brought into wiping contactwith the roller and its coating of adhesive. This apex and the rest of the guides edge force the label into conformity with the profile of the roller and insure the maintenance of the trough formed therein andrthe' resultant-tangential projection of the label beyond the roller whereit may be easily grasped for removal and application. 7

The V-bottom 2 provided in the rectangular tank 1 re duces the quantity of adhesive needed to keep it up to the proper working level on the roller 7. A cover 75, FIG. 2, fitting closely upon the rim of the tank around the roller 7 and recessed to mount upon the feed table, and equipped with lugs 77 to hold it in place, is provided to keep the fluids in the adhesive from evaporating while the paster is 'not in use;

of the tank, as shown in FIG. 3. Thus the tank is held in fixed operative position upon the base 81 with the slotted end 33 of the roller shaft 11 in driving engagement with the output shaft 31 of the motor. Yet the entire device can be instantly lifted off from its base and disconnected from the output shaft, for removal for cleaning or other purposes.

While I have illustrated and described a certain form in which the invention may be embodied, I am aware that many modifications may be made therein by any person skilled in the art, without departing from the scope of the invention as expressed in the claims. Therefore, I do not wish to be limited to the particular form shown, or to the details of construction thereof, but what I do claim is:

1. A label paster having in combination a reservoir for liquid adhesive, a roller of concave profile rotatably mounted therein so as to dip into the adhesive, means for rotating the roller, a feed table having a fiat label-supporting surface disposed in a plane parallel to the rollers axis and intersecting the roller and an edge adjacent the roller matching in contour the shape of the proximate surface portion of the roller, means mounting the table for pivotal movement carrying the edge into adhesive-strippingrelation to the roller, and a guide above and in fixed spaced and parallel relation to the surface of the feed table, adapted to engage the upper surface of a label being slid over the table and roller and force the label into conforming contact with the concave surface of the roller.

2. A label paster having in combination a reservoir for liquid adhesive, a roller of concave profile rotatably mounted therein so as to dip into the adhesive, means for rotating the roller, a tilting feed table having a flat labelsupporting surface and an adhesive-stripping edge fixed thereon in proximity to the rollers surface, a label guide fixed on and extending beyond the end of the table having an edge in spaced and parallel relation to the label-supporting surface adapted to force a label slid along such surface into conformity with the profile of the roller, and cam means to effect the tilting of the table and thereby determine the spaced relation of the guide and the adhesivestripping edge with respect to the rollers surface.

3. A label paster having in combination a reservoir for liquid adhesive, a roller of concave profile rotatably mounted therein so as to dip into the adhesive, means for rotating the roller, a feed table tiltably mounted on the reservoir and having a flat label-supporting surface disposed in a plane parallel to the rollers axis and intersecting the roller, and having a convex edge adjacent the roller matching in contour the shape of the proximate surface portion of the roller, means in connection with the feed table for limiting the thickness of adhesive carried by the roller comprising a scraper positioned in a spaced relation from the surface of the roller that is determined by the degree of tilt of the feed table, and a guide above and in fixed spaced and parallel relation to the surface of the feed table adapted to engage the upper surface of a label being slid over the table and roller and force the label into conforming contact with the concave surface of the roller.

References Cited in the file of this patent UNITED STATES PATENTS 396,711 Richards Jan. 22, 1889 1,224,764 Maltby May 1, 1917 2,573,052 Parker Oct. 30, 1951 3,000,348 Mallet Sept. 19, 1961 3,064,621 Gore Nov. 20, 1962 FOREIGN PATENTS 926,416 France Apr. 21, 1947 130,287 Great Britain July 31, 1919 420,668 Great Britain Dec. 6, 1934 

1. A LABEL PASTER HAVING IN COMBINATION A RESERVOIR FOR LIQUID ADHESIVE, A ROLLER OF CONCAVE PROFILE ROTATABLY MOUNTED THEREIN SO AS TO DIP INTO THE ADHESIVE, MEANS FOR ROTATING THE ROLLER, A FEED TBLE HAVING A FLAT LABEL-SUPPORTING SURFACE DISPOSED IN A PLANE PARALLEL TO THE ROLLER''S AXIS AND INTERSECTING THE ROLLER AND AN EDGE ADJACENT THE ROLLER MATCHING IN CONTOUR THE SHAPE OF THE PROXIMATE SURFACE PORTION OF THE ROLLER, MEANS MOUNTING THE TABLE FOR PIVOTAL MOVEMENT CARRYING THE EDGE INTO ADHESIVE-STRIPPING RELATION TO THE ROLLER, AND A GUIDE ABOVE AND IN FIXED SPACED AND PARALLEL RELATION TO THE SURFACE OF THE FEED TABLE, ADAPTED TO ENGAGE THE UPPER SURFACE OF A LABEL BEING SLID OVER THE TABLE AND ROLLER AND FORCE THE LABEL INTO CONFORMING CONTACT WITH THE CONCAVE SURFACE OF THE ROLLER. 